This invention relates to a novel process for the preparation of hydrocarbon chlorosilanes. That is, the present invention relates to a process for producing high yields of alkyl, alkenyl or aralkyl chlorosilanes by reacting polysilanes (i.e., silicon compounds which contain one or more Si--Si units) with alkyl or alkenyl chloride at a temperature ranging from about 10.degree. C to about 60.degree. C in the presence of amine (or phosphine) and metal salt (or complex) co-catalysts.
U.S. Pat. No. 3,878,234 discloses the preparation of hydrocarbon silanes by reacting methylchloropolysilanes or chloropolysilanes with hydrocarbon chlorides in the presence of a tertiary amine, the chloride salt of a tertiary amine, or a hydrocarbon phosphonium chloride catalyst at a temperature of from 30.degree. to 250.degree. C. However, the yields of hydrocarbon silane disclosed in the examples of that patent varied widely from 0% to 87% depending upon the temperature (75.degree. to 125.degree. C) and catalyst used. The reaction times given in that patent range from 12 to 200 hours.
A recent publication (Journal of Organometallic Chemistry 85, CL (1975)) discloses that halobenzenes can be reacted with disilanes to give arylsilanes in the presence of a palladium complex catalyst. The publication discloses temperatures ranging from 120.degree. C to 170.degree. C and reaction times between 18 and 33 hours. Also, the publication does not disclose reactions using alkyl halides as a reactant.
Another recent publication (Journal of Organometallic Chemistry 96, C1-C3 (1975)) discloses the reaction of allylchloride with trichlorosilane using a stoichiometric amount of a tertiary amine in the presence of a metallic salt catalyst. Such a reaction involves the cleavage of the hydrogen-silicon bond of the trichlorosilane to form allyl trichlorosilane and amine hydrochloride. The amine hydrochloride is regarded to be an undesirable byproduct of the reaction.
U.S. Pat. No. 2,474,087 discloses the reaction of hydrocarbon halides with hexachlorodisilane to produce hydrocarbon halosilanes either without a catalyst or with a cuprous chloride, antimony trichloride, or mercuric chloride catalyst. All examples in that patent disclose reaction temperatures ranging from 200.degree. to 350.degree. C.
U.S. Pat. No. 2,709,176 discloses the reaction of polysilanes with hydrogen chloride in the presence of tertiary amines or their halide salts to produce silanes having a higher SiH content than that contained in the reactants. This reaction does not establish any new silicon-carbon bonds but merely establishes silicon-hydrogen and silicon-chlorine bonds.
U.S. Pat. Nos. 2,598,435 and 2,842,580 disclose the rearrangement of methyl and chlorine substituted silanes to produce monosilane and polysilanes. In this reaction no new carbon-silicon bonds are formed except by rearrangement.